CyberRota Analysis
AI-GeneratedThe vulnerability in the zbus_polkit crate arises from a type mismatch in the encoding of the UID, leading to the silent discarding of the caller-supplied UID during authorization checks. This flaw allows a local unprivileged attacker to exploit a time-of-check/time-of-use race condition, potentially gaining unauthorized access by impersonating the identity of a terminated process. Organizations using affected versions of zbus_polkit should prioritize remediation to prevent unauthorized actions by malicious actors.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
Subject::new_for_owner() in the zbus_polkit crate encodes the uid entry of a unix-process polkit subject as an unsigned 32-bit integer (D-Bus type u), whereas the org.freedesktop.PolicyKit1.Authority interface specifies a signed 32-bit integer (D-Bus type i). Because of this type mismatch, polkit silently discards the caller-supplied UID and instead determines the subject's owner itself by looking up the PID in /proc, a lookup that is inherently subject to a time-of-check/time-of-use race. Consequently, an application that passes a UID obtained from a trustworthy source — for example SO_PEERCRED Unix socket peer credentials — in order to defend against PID reuse receives no protection, and the supplied UID has no effect on the authorization decision. A local unprivileged attacker who can cause an authorized process to terminate and then win the race to have their own process assigned the same PID can be authorized under the identity of the terminated process, bypassing the polkit authorization check and performing actions the attacker is not entitled to. This issue affects zbus_polkit before 5.1.0.